1. Field of the Invention
The present invention relates to a document editing apparatus which performs automatic line advancement in response to a key entry made at a character position near the end of a text line, and particularly to a document editing apparatus capable of splitting a word into segments and placing the word segments at the tail of the first line and the head of the second line of two consecutive text lines.
2. Description of Related Art
A conventional document editing apparatus operative to split a displayed character string, i.e., a word, into segments and display the word segments continuously on two text lines based on the operator's response is disclosed in Japanese Patent Laid-open No. 63-20661, for example. This technique is designed to evaluate the size of a blank portion at the line end, which would be created if space characters used between words on the text line were reduced in size and the text line were left justified, and display the number of characters, which can be moved to the created blank portion, at the top of the next line. The operator is informed of the maximum number of characters, out of the leading word on the next line, which can be moved to the blank portion of the preceding line, so that the operator knows the range of possible word split positions for the leading word on the next line.
In general, when a word is split into two segments displayed on two consecutive lines, a hyphen is attached to the end of the former segment to indicate that the two segments form a complete word. The word split position, i.e., the position of hyphenation, is not arbitrary, as each word has legitimate split position(s) depending on syllables and meaning of the word.
The conventional document editing apparatus, however, merely displays the number of characters which can be moved to the preceding text line, and therefore the operator is obliged to determine the best position of word segmentation and hyphenation in moving a word segment to the preceding text line on each occasion. For this reason, a wrong word split position can possibly be selected and considerable time expended before the operator chooses or determines a proper word split position.
The "IBM Technical Disclosure Bulletin", Vol.29, No.1, pp.383-384, published in June 1986, describes the function of hyphenation based on a dictionary. However, this hyphening function simply inserts a hyphen in a word in accordance with the dictionary, and it sets a hyphening position without any consideration of the number of characters of the word and the number of characters which can be placed at the end of the preceding text line. Accordingly, the operator must decide on hyphenation through the assessment of the matching between the number of characters of the former word segment and the number of characters which can stay at the end of the preceding text line by counting the characters. Consequently, the operator spends a lot of time selecting the proper hyphening position.